Differentiation of Veillonella atypica, Veillonella dispar and Veillonella parvula using restricted fragment-length polymorphism analysis of 16S rDNA amplified by polymerase chain reaction

Spondylodiscitis due to anaerobic bacteria Veillonella parvula: Case report and literature review

Background:

While pyogenic spondylodiscitis due to Gram-positive aerobic bacteria and its treatment is well known, spondylodiscitis caused by anaerobic Gram-negative pathogen is rare. In particular, the spondylodiscitis caused by Veillonella species is an absolute rarity. Thus no established management recommendations exist.

Case Description:

A case report of a 79-year-old man with spondylodiscitis caused by Veillonella parvula with intramuscular abscess collection managed conservatively with stand-alone antibiotic therapy without a spinal stabilization procedure. A review of literature of all reported spondylodiscitis caused by Veillonella species was performed. After 3 week-intravenous therapy with the ceftriaxone in combination with the metronidazole followed by 3 weeks per oral therapy with amoxicillin/clavulanate, the complete recovery of the patient with the V. parvula infection was achieved.

Conclusion:

Treatment of the spondylodiscitis caused by Veillonella species should contain a beta-lactam with beta-lactamase inhibitor or third-generation cephalosporine. Six weeks of treatment seem to be sufficient for the complete recovery of the patient.

Veillonellaceae family members uniquely alter the cervical metabolic microenvironment in a human three-dimensional epithelial model

Bacterial vaginosis (BV) is a gynecologic disorder characterized by a shift in cervicovaginal microbiota from Lactobacillus spp. dominance to a polymicrobial biofilm composed of diverse anaerobes. We utilized a well-characterized human three-dimensional cervical epithelial cell model in conjunction with untargeted metabolomics and immunoproteomics analyses to determine the immunometabolic contribution of three members of the Veillonellaceae family: Veillonella atypica, Veillonella montpellierensis and Megasphaera micronuciformis at this site. We found that Veillonella spp. infections induced significant elevation of polyamines. M. micronuciformis infections significantly increased soluble inflammatory mediators, induced moderate levels of cell cytotoxicity, and accumulation of cell membrane lipids relative to Veillonella spp. Notably, both V. atypica and V. montpellierensis infections resulted in consumption of lactate, a key metabolite linked to gynecologic and reproductive health. Collectively our approach and data provide unique insights into the specific contributions of Veillonellaceae members to the pathogenesis of BV and women's health.

Composition and diversity of the subgingival microbiome and its relationship with age in postmenopausal women: an epidemiologic investigation

BACKGROUND

The extent to which the composition and diversity of the oral microbiome varies with age is not clearly understood.

METHODS

The 16S rRNA gene of subgingival plaque in 1219 women, aged 53-81 years, was sequenced and its taxonomy annotated against the Human Oral Microbiome Database (v.14.5). Composition of the subgingival microbiome was described in terms of centered log(2)-ratio (CLR) transformed OTU values, relative abundance, and prevalence. Correlations between microbiota abundance and age were evelauted using Pearson Product Moment correlations. P-values were corrected for multiple testing using the Bonferroni method.

RESULTS

Of the 267 species identified overall, Veillonella dispar was the most abundant bacteria when described by CLR OTU (mean 8.3) or relative abundance (mean 8.9%); whereas Streptococcus oralis, Veillonella dispar and Veillonella parvula were most prevalent (100%, all) when described as being present at any amount. Linear correlations between age and several CLR OTUs (Pearson r = - 0.18 to 0.18), of which 82 (31%) achieved statistical significance (P < 0.05). The correlations lost significance following Bonferroni correction. Twelve species that differed across age groups (each corrected P < 0.05); 5 (42%) were higher in women ages 50-59 compared to ≥70 (corrected P < 0.05), and 7 (48%) were higher in women 70 years and older.

CONCLUSIONS

We identified associations between several bacterial species and age across the age range of postmenopausal women studied. Understanding the functions of these bacteria could identify intervention targets to enhance oral health in later life.

Identification of Veillonella Species in the Tongue Biofilm by Using a Novel One-Step Polymerase Chain Reaction Method

Six Veillonella species have been frequently isolated from human oral cavities including infectious sites. Recently, it was reported that diet, smoking, and possibly socioeconomic status can influence the bacterial profile in oral cavities. In addition, oral hygiene habits may also influence oral microbiota in terms of both numbers and diversity of microorganisms. In this study, the identification of Veillonella species in tongue biofilms of Thai children, divided into three groups dependent on their status of oral hygiene. For this, we used a novel one-step PCR method with species-specific primer sets based on sequences of the rpoB gene. As shown in the results, the number of isolates of Veillonella species was 101 strains from only 10 of 89 subjects. However, the total number of bacteria was high for all subjects. Since it was reported in previous studies that Veillonella species were easy to isolate in human tongue biofilms at high numbers, the results obtained in this study may suggest country- or age-specific differences. Moreover, Veillonella species were detected predominantly in subjects who had poor oral hygiene compared to those with good or moderate oral hygiene. From these results, there is a possibility that Veillonella species may be an index of oral hygiene status. Furthermore, V. rogosae was a predominant species in tongue biofilms of Thai children, whereas V. parvula and V. denticariosi were not isolated at all. These characteristics of the distribution and frequency of Veillonella species are similar to those reported in previous studies. Although further studies are needed in other countries, in this study, a successful novel one-step PCR method was established to detect Veillonella species in human oral cavities easily and effectively. Furthermore, this is the first report investigating the distribution and frequency of Veillonella species in tongue biofilms of Thai children.

Meta-omics uncover temporal regulation of pathways across oral microbiome genera during in vitro sugar metabolism

Dental caries, one of the most globally widespread infectious diseases, is intimately linked to pH dynamics. In supragingival plaque, after the addition of a carbohydrate source, bacterial metabolism decreases the pH which then subsequently recovers. Molecular mechanisms supporting this important homeostasis are poorly characterized in part due to the fact that there are hundreds of active species in dental plaque. Only a few mechanisms (for example, lactate fermentation, the arginine deiminase system) have been identified and studied in detail. Here, we conducted what is to our knowledge, the first full transcriptome and metabolome analysis of a diverse oral plaque community by using a functionally and taxonomically robust in vitro model system greater than 100 species. Differential gene expression analyses from the complete transcriptome of 14 key community members revealed highly varied regulation of both known and previously unassociated pH-neutralizing pathways as a response to the pH drop. Unique expression and metabolite signatures from 400 detected metabolites were found for each stage along the pH curve suggesting it may be possible to define healthy and diseased states of activity. Importantly, for the maintenance of healthy plaque pH, gene transcription activity of known and previously unrecognized pH-neutralizing pathways was associated with the genera Lactobacillus, Veillonella and Streptococcus during the pH recovery phase. Our in vitro study provides a baseline for defining healthy and disease-like states and highlights the power of moving beyond single and dual species applications to capture key players and their orchestrated metabolic activities within a complex human oral microbiome model.

Epidural abscess caused by Veillonella parvula: Case report and review of the literature

Veillonella parvula, an anaerobic, Gram-negative coccus is part of the normal flora of the oral, gastrointestinal, respiratory, and genitourinary tracts in humans and animals. We herein present a case of epidural abscess caused by V. parvula in a 68-year-old man with sinus squamous cell carcinoma who presented with a 3-week history of low back pain. Blood and pus cultures were positive for Veillonella spp. After sequencing of the 16S ribosomal DNA, the pathogen was identified as V. parvula. Surgical debridement was performed following which the patient received intravenous administration of amoxicillin/clavulanate. To our knowledge, there are only seven reported cases of spinal infection caused by Veillonella spp. and these are reviewed here.

Identification of Veillonella tobetsuensis in tongue biofilm by using a species-specific primer pair

Veillonella atypica, Veillonella denticariosi, Veillonella dispar, Veillonella parvula, and Veillonella rogosae have been reported to be isolated from human oral cavities. The recently detected Veillonellatobetsuensis in human tongue biofilms was proposed as a novel Veillonella sp. In this study, to determine the distribution and frequency of V. tobetsuensis, we established a method for the detection and identification of V. tobetsuensis by using polymerase chain reaction (PCR) using a species-specific primer pair. The primer pair for V. tobetsuensis was designed on the basis of the nucleotide sequence of the 70-kDa heat shock protein (dnaK) gene of V. tobetsuensis JCM 17976(T) (=ATCC BAA-2400(T)). The primer pair generated a specific PCR product for V. tobetsuensis but not for other oral Veillonella spp. With the PCR procedure using the primer pair, we could detect less than 10 ng of genomic DNA extracted from V. tobetsuensis. Thus, the PCR method using this primer pair is suitable for the specific detection and identification of V. tobetsuensis. The distribution and frequency of V. tobetsuensis were investigated by PCR using this species-specific primer pair. V. tobetsuensis was detected in 5 of 27 subjects. V. tobetsuensis was recovered from 19% (5/27) of subjects with other Veillonella species. And, prevalence of V. tobetsuensis ranged from 7.6% to 20.0% in these subjects. V. tobetsuensis is likely to coexist with other Veillonella spp. in tongue biofilm. In this study, the species-specific PCR primer pair for V. tobetsuensis was designed using partial sequences of the dnaK gene. This is the first report using a species-specific primer pair for PCR to determine the distribution and frequency of V. tobetsuensis in tongue biofilm.

The distribution and frequency of oral veillonella spp. in the tongue biofilm of healthy young adults

Five species of oral Veillonella, V. atypica, V. denticariosi, V. dispar, V. parvula, and V. rogosae, have been suggested to be early colonizers of dental biofilm and causes of opportunistic infections and oral malodor. However, the pathogenicity and the distribution of oral Veillonella spp. have not been clarified. Previously, oral Veillonella spp. were identified by using 16S rDNA sequence analysis. In addition, recently, Veillonella isolates from human tongue biofilm were identified by rpoB gene sequences, but these procedures are time-consuming and complex. To overcome this problem, Igarashi et al. have designed species-specific primer sets for oral Veillonella spp. by using a highly variable region in the rpoB gene. In the present study, the distribution and frequency of oral Veillonella spp. in the tongue biofilm of healthy adults in their 20s were examined by using these species-specific primer sets. Tongue biofilms of these subjects were found to be divided into two groups based on the distribution and frequency of oral Veillonella spp. In one group, V. rogosae was the predominant species; the other group consisted of mainly V. dispar and V. atypica. Multiple factors may influence these differences in distribution and frequency of oral Veillonella spp. in tongue biofilm. This is the first report also demonstrating the availability of the species-specific primer sets for PCR to determine the distribution and frequency of oral Veillonella spp. in the tongue biofilm of healthy adults in their 20s.

Veillonella spondylodiscitis in a healthy 76-year-old lady

PURPOSE

To report a case of Veillonella spondylodiscitis in a healthy 76-year-old lady.

METHODS

A previously healthy 76-year-old lady presented with worsening axial back pain at the thoracolumbar junction, fever and loss of weight. Examination revealed deep tenderness over the thoracolumbar junction with painful and restricted spinal movements. The lower limb motor power, sensation and reflexes were normal.

RESULTS

Radiographs of the lumbosacral spine showed evidence of spinal instability with lateral translation and loss of disc space at L1-L2. MRI scans revealed fluid intensity within the L1-L2 disc with infective debris elevating the posterior longitudinal ligament and narrowing the spinal canal. Both tissue and blood cultures were positive for the anaerobic organism, Veillonella. A staged anterior-posterior spinal surgery followed by an extended course of antibiotics resulted in the clinical improvement and normalisation of blood parameters. A review of the literature on Veillonella infections is also presented.

CONCLUSION

The aim of this report is to bring Veillonella spondylodiscitis to the attention of spinal surgeons and infectious disease specialists and discuss the management options.

Identification of oral species of the genus Veillonella by polymerase chain reaction

INTRODUCTION

Members of the genus Veillonella cannot be reliably distinguished by their biochemical characteristics and phenotypic features. Moreover, DNA-DNA hybridization and sequence analyses of the 16S ribosomal RNA gene including random fragment length polymorphism analysis, are complex and time-consuming procedures that are not well-suited to identifying oral species of Veillonella: Veillonella atypica, Veillonella denticariosi, Veillonella dispar, Veillonella parvula, and Veillonella rogosae.

METHODS

In this study, five forward primers and a reverse primer were designed for polymerase chain reaction (PCR) according to the partial sequences of the rpoB genes of these oral Veillonella species.

RESULTS

The forward primers were species-specific for these five Veillonella species, and could produce specific amplicons when used together with reverse primer and individual DNA templates of these species in PCR. These primer pairs were also found to discriminate between the respective species, and the Veillonella strains isolated from human oral cavities were successfully assigned to one of the five oral species of the genus Veillonella based on their specific products by PCR.

CONCLUSION

A simple two-step PCR procedure using the five sets of primer pairs developed in the present study is a rapid and reliable method for the identification of the recognized oral Veillonella species.

Diversity of Veillonella spp. from sound and carious sites in children

Detailed data on the distribution of Veillonella in caries-free and caries-active subjects are scarce. We hypothesized that the diversity of the genus would be lower in caries lesions than in plaque from caries-free individuals. The proportions of Veillonella were not significantly different in the two groups. All isolates (n = 1308) were genotyped by REP-PCR, and different genotypes (n = 170) were identified by 16S rRNA, dnaK, and rpoB sequencing. V. parvula, V. dispar, and V. atypica were in both groups, V. denticariosi only in caries lesions, and V. rogosae only from the caries-free individuals (p < 0.009). Lesions were more likely to harbor a single predominant species (p = 0.0018). The mean number of genotypes in the lesions was less than in the fissure (p < 0.001) or buccal (p = 0.011) sites. The Veillonella from caries-free sites were more diverse than those from caries lesions, and may be related to the acidic environment of caries lesions.

Asaccharolytic anaerobic gram-negative coccobacilli (AAGNC) isolated from infected root canals and periodontal pockets

BACKGROUND/AIMS

Culture-difficult bacteria, including asaccharolytic anaerobic gram-negative coccobacilli (AAGNC), may constitute a predominant group of organisms in oral sites. This study aimed to characterize phylogenetically 10 AAGNC isolated from endodontic lesions and periodontal pockets.

METHODS

16S rDNA sequence and G + C content were determined. Strains sharing more than 98% sequence similarities and similar G + C content were considered the same bacterial species.

RESULTS

One isolate resembled Dialister pneumosintes (the type species of the genus Dialister) with 35 mol% G + C content and 97% sequence similarity. Of eight isolates having 45-47 mol% G + C content, seven were identified as D. invisus and one resembled Dialister invisus with 97% sequence similarity. However the 16S rDNA sequence similarities with D. pneumosintes were relatively low, indicating the strains may belong to a new genus. The last isolate revealed 35 mol% G + C content, but had higher 16S rDNA sequence similarity with D. invisus than with D. pneumosintes.

CONCLUSION

The group of oral AAGNC isolates need to be reclassified.

Veillonella montpellierensis sp. nov., a novel, anaerobic, Gram-negative coccus isolated from human clinical samples

Three strains of a hitherto unknown, Gram-negative, anaerobic coccus were isolated from human samples. At the phenotypic level, the isolates displayed all the characteristics of bacteria belonging to the genus Veillonella. Sequence analysis revealed that the three strains shared >99·5 % similarity in 16S rDNA sequence and >98·4 % similarity in dnaK sequence. The three unknown strains formed a separate subclade that was clearly remote from Veillonella species of human and animal origin. Based on these results, the three strains were considered to represent a novel species within the genus Veillonella, for which the name Veillonella montpellierensis is proposed. The type strain of the species is ADV 281.99T (=CIP 107992T=CCUG 48299T).

Intra-chromosomal heterogeneity between the four 16S rRNA gene copies in the genus Veillonella: implications for phylogeny and taxonomy

Among the seven species characterized within the genus Veillonella, three (Veillonella dispar, Veillonella parvula and Veillonella atypica) have so far been isolated from human flora and during infectious processes. Sequencing and analysis of 16S rDNA (rrs) has been described as the best method for identification of Veillonella strains at the species level since phenotypic characteristics are unable to differentiate between species. rrs sequencing for the three species isolated from humans showed more than 98 % identity between them. Four rrs copies were found in the reference strains and in all the clinical isolates studied. The sequences of each rrs were determined for the clinical strain ADV 360.1, and they showed a relatively high level of heterogeneity (1.43 %). In the majority of cases, polymorphic positions corresponded to nucleotides allowing differentiation between the three species isolated from humans. Moreover, variability observed between rrs copies was higher than that between 16S rDNA sequences of V. parvula and V. dispar. Phylogenetic analysis showed that polymorphism between rrs copies affected the position of strain ADV 360.1 in the tree. Variable positions occurred in stems and loops belonging to variable and hypervariable regions of the 16S rRNA secondary structure but did not change the overall structure of the 16S rRNA. PCR-RFLP experiments performed on 27 clinical isolates of Veillonella sp. suggested that inter-rrs heterogeneity occurs widely among the members of the genus VEILLONELLA: These results, together with the lack of phenotypic criteria for species differentiation, give preliminary arguments for unification of V. dispar and V. parvula.

Restriction fragment-length polymorphism analysis of 16S ribosomal RNA genes amplified by polymerase chain reaction for rapid identification of cultivable oral treponemes

Although oral treponemes are among the most frequently found bacteria in periodontal pockets, identification of these organisms can be difficult. In this study, restriction fragment-length polymorphism (RFLP) analysis of polymerase chain reaction (PCR)-amplified 16S ribosomal RNA genes (16S rRNA gene PCR-RFLP) was used to generate restriction profiles of reference strains of oral treponemes including Treponema denticola, Treponema socranskii, Treponema vincentii. Treponema pectinovorum and Treponema medium as well as for Treponema phagedenis and Treponema pailidum and five treponeme strains isolated from human peridontal pockets. Before RFLP analysis, the 16S rRNA gene sequences were obtained from the GenBank database, and the analysis of the theoretical banding patterns for HpaII suggested good species discrimination. 16S rRNA gene sequences were amplified from isolated genomic DNA samples by PCR with spirochete-specific primers. The PCR products were then purified and characterized by single digestion with restriction endonuclease HpaII, and this allowed discrimination between the respective reference strains. Five clinical isolates, four T. denticola and one T. socranskii, were assigned on the basic of their restriction profiles by digestion with HpaII. 16S rRNA gene PCR-RFLP using HpaII is a rapid and reliable method for differentiation of cultivable oral treponemes.